Numerical simulation of chloride-induced reinforcement corrosion in cracked concrete based on mesoscopic model.

A mesoscopic model is proposed to investigate the combined effects of coarse aggregates (CA) and cracks on mass transport and corrosion of steel bars in concrete under chloride exposure. The accuracy of the model is validated using existing experimental data. Additionally, the corrosion morphology, depth, and quantity throughout the lifespan of the models are calculated and analyzed. The results indicate that both cracks and CA enhance the non-uniformity of corrosion morphology, displaying convexities-concavities and heart-shaped characteristics, although they play a varying role of inhibition or acceleration effects in influencing the corrosion rate, respectively. When it exceeds 0.05 mm, widths of cracks dominate the accelerated corrosion process of initiation and propagation stages, whereas CA controls the final corrosion rate at the overall corrosion stage. Furthermore, a simplified equation is proposed to predict the residual area of steel bars, offering a reference for evaluating the corrosion state of steel bars in cracked concrete. • Establishment of a mesoscopic model considering the coupling effects of volume fraction of aggregate and cracks width. • Predict the mass transportation (chloride ions and oxygen) conditions in concrete and corrosion morphology of steel bars. • Revelation of coupling influence of aggregates' inhibited and cracks' accelerated effect on the corrosion condition of steel bars. • Proposed an equation to predict the residual area of steel bars in concrete with different crack width at any time. [ABSTRACT FROM AUTHOR]